A SCIENTIFIC EXPLANATION OF LIFE 79 



questions I might ask, from the man of science I should receive answers 

 which, though differing in richness of detail, in principal would be 

 invariable. 



"What is this principle? No matter how much the physicist, the 

 chemist and the meteorologist might add to the chain of events as 

 outlined, it would never be other than a chain of events. Even at the 

 present time it might be lengthened almost indefinitely, and although 

 this might show how much we know, it would also show no less clearly 

 that all our knowledge is of one sort, and that scientific explanations, 

 however many or few links we may have in our chains, never amount to 

 more than the enumeration of the conditions under which the events 

 in nature take place. Under the proper conditions evaporation occurs ; 

 when the conditions are right a cloud is formed; and, under the 

 proper circumstances, rain falls. This is the chain; in it one event is 

 the outcome of certain conditions and on its shoulders stands the next 

 event if other conditions no less important have been satisfied. 



There is something very instructive about a series of this kind, for 

 study, not only of the conditions under which rain falls, but of the 

 conditions under which anything whatever happens in nature, shows 

 conclusively that all the conditions are equal in importance. We our- 

 selves are such poor democrats, however, and so accustomed to special 

 privileges, so much more interested in some things than in others, so 

 inured to our worship of the exceptional and the peculiar, that when 

 we meet with a situation like this, the language of the street, the habit 

 of a life-time, and the teaching of centuries all unfit us for the task 

 of interpreting nature as she really is. Nature is democratic; that 

 which is the condition of an event is neither more nor less than that 

 event's condition, and when, as is always the case, a group of conditions 

 is the basis of an event, that event is suspended, or another takes its 

 place, unless the tiniest condition has cast its vote in the primaries. 



It is the neglect of this truth that leads to many of the difficulties 

 of science, for her most ardent votaries are often bent on bestowing 

 special favors among conditions, and now and again knight them. But 

 knighthood among conditions is as precarious an honor in science, as a 

 seat in the house of lords, for sooner or later the bogus knight falls in 

 joust, and another, himself soon to be vanquished, takes his place. It 

 has happened many times in the history of science, one need but think 

 of the changes in the treatment of disease that first one cause, then 

 another then a third has been assigned the leading role in the drama 

 of causation, but each of these in turn has had his vizor torn off, and 

 has stood exposed as a condition which, masquerading under the armor 

 of special privilege, for a time succeeded in imposing on the public as 

 a real cause. Indeed, no one who has set out on the quest for causes in 

 science, has ever returned with anything else than a knowledge of 



